Crack propagation in fatigue

Stress corrosion (see Section 2.3.4), in particular accelerated crack propagation in fatigue (see Section 2.3.5). 

Remarkably little has been published on corrosion fatigue crack propagation in copper and its alloys. In general little or no influence of marine environments has been observed in crack propagation experiments on manganese and nickel-aluminium bronzes although the frequencies employed were quite high (> 2.5 Hz) ... 

Stewart, A. T., Effect of hydrogen on fatigue crack propagation in steels , Proc. Int. Conf. on Mechanisms of Environment Sensitive Cracking in Materials, University of Surrey, 4-7 April 1977, The Metals Society, pp. 400-11 (1977)... 

James, L. A., Fatigue crack propagation in Austenitic stainless steel . Atomic Energy Review 14, 37-86 (1976)... 

Ritchie, R. O., Near threshold fatigue crack propagation in steels . International Metals Reviews, Nos. 5 and 6, pp. 205-230 (1979)... 

The NACE publication Corrosion Fatigue gives a comprehensive account of all aspects of the subject, and in this work a review of the application of fracture mechanics for studying the phenomenon has been presented by McEvily and Wei , whilst Kitagawa has given a detailed account of crack propagation in unnotched steel specimens. This work should be consulted for details of testing and interpretation of results. 

Crack propagation. The effect of the environment on crack propagation in corrosion fatigue can lead to increase in the crack growth rate. Three types of behavior have been reported.95,105... 

M. J. Reece, F. Guiu, and M. F. R. Sammur, Cyclic Fatigue Crack Propagation in Alumina under Direct Tension-Compression Loading, J. Am. Ceram. Soc., 72[2], 348-352 (1990). 

Altstadt V (1997) Fatigue crack propagation in homopolymers and blends with high and low interphase strength. In European Conference on Macromolecular Physics -Surfaces and Interfaces in Polymers and Composites, Lausanne, Switzerland... 

Materials science associated with fracture mechanics has mainly been confined to composite materials such as concrete, ceramics and metals. Much of the emphasis of the research has been on preventing fatigue and failure rather than designing for it to occur. The way a structure deforms and breaks under stress is crucial for properties such as flow and fracture behaviour, sensory perception of structure, water release and the mobility and release of active compounds. In the case of foods, the ability to break down and interact with the mouth surfaces provides texture and taste attributes. The crack propagation in a complex supramolecular structure is highly dependent on the continuous matrix, interfacial properties and defects and the heterogeneity of the structure. Previous structure-fracture work has dealt with cellular plant foods, and it has been demonstrated that the fracture path differs between fresh and boiled carrots due to cellular adhesion and cell wall strength as well as cell wall porosity and fluid transport (Thiel and Donald 1998 Stoke and Donald 2000 Lillford 2000). 

In the literature on fatigue crack propagation in metals and, later, in polymers it has been well documented that fracture surfaces can exhibit ripple markings which are due to the cyclic loading process. 

Many investigations of the mechanical properties of ABS and of the nature of rubber toughening in this material have been made and these findings are reviewed and discussed by Bucknall and by Mann and Williamson There have been fewer studies of fatigue performance, and most of these are concerned only with crack propagation in notched specimens Here we are concerned with the... 

Fig. 4.4. Schematic representation of the two modes of fatigue crack propagation in polymers...

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